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Thomas-Joulié A, Tran S, El Houari L, Seyve A, Bielle F, Birzu C, Lozano-Sanchez F, Mokhtari K, Giry M, Marie Y, Laigle-Donadey F, Dehais C, Houillier C, Psimaras D, Alentorn A, Laurenge A, Touat M, Sanson M, Hoang-Xuan K, Kas A, Rozenblum L, Habert MO, Nichelli L, Leclercq D, Galanaud D, Jacob J, Karachi C, Capelle L, Carpentier A, Mathon B, Belin L, Idbaih A. Prognosis of glioblastoma patients improves significantly over time interrogating historical controls. Eur J Cancer 2024; 202:114004. [PMID: 38493668 DOI: 10.1016/j.ejca.2024.114004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/01/2024] [Accepted: 03/01/2024] [Indexed: 03/19/2024]
Abstract
BACKGROUND Glioblastoma (GBM) is the most common devastating primary brain cancer in adults. In our clinical practice, median overall survival (mOS) of GBM patients seems increasing over time. METHODS To address this observation, we have retrospectively analyzed the prognosis of 722 newly diagnosed GBM patients, aged below 70, in good clinical conditions (i.e. Karnofsky Performance Status -KPS- above 70%) and treated in our department according to the standard of care (SOC) between 2005 and 2018. Patients were divided into two groups according to the year of diagnosis (group 1: from 2005 to 2012; group 2: from 2013 to 2018). RESULTS Characteristics of patients and tumors of both groups were very similar regarding confounding factors (age, KPS, MGMT promoter methylation status and treatments). Follow-up time was fixed at 24 months to ensure comparable survival times between both groups. Group 1 patients had a mOS of 19 months ([17.3-21.3]) while mOS of group 2 patients was not reached. The recent period of diagnosis was significantly associated with a longer mOS in univariate analysis (HR=0.64, 95% CI [0.51 - 0.81]), p < 0.001). Multivariate Cox analysis showed that the period of diagnosis remained significantly prognostic after adjustment on confounding factors (adjusted Hazard Ratio (aHR) 0.49, 95% CI [0.36-0.67], p < 0.001). CONCLUSION This increase of mOS over time in newly diagnosed GBM patients could be explained by better management of potentially associated non-neurological diseases, optimization of validated SOC, better management of treatments side effects, supportive care and participation in clinical trials.
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Affiliation(s)
- A Thomas-Joulié
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France; AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service d'Oncologie-Radiothérapie, F-75013 Paris, France
| | - S Tran
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuropathologie-Escourolle, F-75013 Paris, France
| | - L El Houari
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Unité de Recherche Clinique, F-75013 Paris, France
| | - A Seyve
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - F Bielle
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuropathologie-Escourolle, F-75013 Paris, France
| | - C Birzu
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - F Lozano-Sanchez
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - K Mokhtari
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuropathologie-Escourolle, F-75013 Paris, France
| | - M Giry
- Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, F-75013 Paris, France
| | - Y Marie
- Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, F-75013 Paris, France
| | - F Laigle-Donadey
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - C Dehais
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - C Houillier
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - D Psimaras
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - A Alentorn
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - A Laurenge
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - M Touat
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - M Sanson
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - K Hoang-Xuan
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France
| | - A Kas
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Médecine Nucléaire, F-75013 Paris, France; Laboratoire d'Imagerie Biomédicale, Sorbonne Université, CNRS, INSERM, 75006 Paris, France
| | - L Rozenblum
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Médecine Nucléaire, F-75013 Paris, France; Laboratoire d'Imagerie Biomédicale, Sorbonne Université, CNRS, INSERM, 75006 Paris, France
| | - M-O Habert
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Médecine Nucléaire, F-75013 Paris, France; Laboratoire d'Imagerie Biomédicale, Sorbonne Université, CNRS, INSERM, 75006 Paris, France
| | - L Nichelli
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuroradiologie, F-75013 Paris, France
| | - D Leclercq
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuroradiologie, F-75013 Paris, France
| | - D Galanaud
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuroradiologie, F-75013 Paris, France
| | - J Jacob
- AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service d'Oncologie-Radiothérapie, F-75013 Paris, France
| | - C Karachi
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurochirurgie, F-75013 Paris, France
| | - L Capelle
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurochirurgie, F-75013 Paris, France
| | - A Carpentier
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurochirurgie, F-75013 Paris, France
| | - B Mathon
- Sorbonne Université, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurochirurgie, F-75013 Paris, France
| | - L Belin
- Sorbonne Université, INSERM, Institut Pierre Louis d'Epidémiologie et de Santé Publique, AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière - Charles Foix, Département de Santé Publique, Unité de Recherche Clinique Pitié-Salpêtrière-Charles Foix, Paris, France
| | - A Idbaih
- Sorbonne Université, Inserm, CNRS, UMR S 1127, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neurologie-Oncologie, F-75013 Paris, France; Sorbonne Université, INSERM, Institut Pierre Louis d'Epidémiologie et de Santé Publique, AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière - Charles Foix, Département de Santé Publique, Unité de Recherche Clinique Pitié-Salpêtrière-Charles Foix, Paris, France.
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Raja H, Munawar A, Mylonas N, Delsoz M, Madadi Y, Elahi M, Hassan A, Abu Serhan H, Inam O, Hernandez L, Chen H, Tran S, Munir W, Abd-Alrazaq A, Yousefi S. Automated Category and Trend Analysis of Scientific Articles on Ophthalmology Using Large Language Models: Development and Usability Study. JMIR Form Res 2024; 8:e52462. [PMID: 38517457 PMCID: PMC10998173 DOI: 10.2196/52462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 01/22/2024] [Accepted: 02/02/2024] [Indexed: 03/23/2024] Open
Abstract
BACKGROUND In this paper, we present an automated method for article classification, leveraging the power of large language models (LLMs). OBJECTIVE The aim of this study is to evaluate the applicability of various LLMs based on textual content of scientific ophthalmology papers. METHODS We developed a model based on natural language processing techniques, including advanced LLMs, to process and analyze the textual content of scientific papers. Specifically, we used zero-shot learning LLMs and compared Bidirectional and Auto-Regressive Transformers (BART) and its variants with Bidirectional Encoder Representations from Transformers (BERT) and its variants, such as distilBERT, SciBERT, PubmedBERT, and BioBERT. To evaluate the LLMs, we compiled a data set (retinal diseases [RenD] ) of 1000 ocular disease-related articles, which were expertly annotated by a panel of 6 specialists into 19 distinct categories. In addition to the classification of articles, we also performed analysis on different classified groups to find the patterns and trends in the field. RESULTS The classification results demonstrate the effectiveness of LLMs in categorizing a large number of ophthalmology papers without human intervention. The model achieved a mean accuracy of 0.86 and a mean F1-score of 0.85 based on the RenD data set. CONCLUSIONS The proposed framework achieves notable improvements in both accuracy and efficiency. Its application in the domain of ophthalmology showcases its potential for knowledge organization and retrieval. We performed a trend analysis that enables researchers and clinicians to easily categorize and retrieve relevant papers, saving time and effort in literature review and information gathering as well as identification of emerging scientific trends within different disciplines. Moreover, the extendibility of the model to other scientific fields broadens its impact in facilitating research and trend analysis across diverse disciplines.
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Affiliation(s)
- Hina Raja
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Asim Munawar
- Watson Research Center, IBM Research, New York, NY, United States
| | - Nikolaos Mylonas
- School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Mohammad Delsoz
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Yeganeh Madadi
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Muhammad Elahi
- Quillen College of Medicine, East Tennessee State University, Johnson, TN, United States
| | - Amr Hassan
- Gavin Herbert Eye Institute, School of Medicine, University of California, Irvine, CA, United States
| | | | - Onur Inam
- Edward S. Harkness Eye Institute, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, United States
- Department of Biophysics, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Luis Hernandez
- Association to Prevent Blindness in Mexico, Ciudad, Mexico
| | - Hao Chen
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, United States
- Department of Pharmacology, Addiction Science and Toxicology, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Sang Tran
- Department of Ophthalmology and Visual Sciences, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Wuqaas Munir
- Department of Ophthalmology and Visual Sciences, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Alaa Abd-Alrazaq
- AI Center for Precision Health, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Siamak Yousefi
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN, United States
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3
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Sigman B, Linder DF, Waller JL, Bollag WB, Baer SL, Tran S, Kheda M, Young L, Mohammed A, Isales CM, Siddiqui B. Hashimoto's thyroiditis and renal transplant rejection. J Endocrinol Invest 2023; 46:2125-2132. [PMID: 37012521 DOI: 10.1007/s40618-023-02065-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/09/2023] [Indexed: 04/05/2023]
Abstract
PURPOSE Hashimoto's thyroiditis (HT) is a common autoimmune thyroid disorder that can disrupt thyroid function and homeostasis. As HT results from a dysregulated immune system, we hypothesized that these patients might be more susceptible to transplant failure; however, literature on this association is limited. The purpose of this study is to examine the association of HT with the risk of renal transplant failure. METHODS We utilized the United States Renal Database System dataset collected from 2005 to 2014 and compared the time from first renal transplant to transplant failure in end-stage renal disease (ESRD) patients with a HT diagnosis to ESRD patients without a HT diagnosis that underwent renal transplant. RESULTS A total of 144 ESRD patients had International Classification of Disease-9 claim codes for HT prior to renal transplant, amongst a total cohort of 90,301 renal transplant patients aged 18-100 and meeting criteria. Patients with HT were significantly more likely to be female, white, and to have a diagnosis of cytomegalovirus compared to patients without. ESRD patients with a HT diagnosis that underwent renal transplant had a significantly increased risk of renal transplant failure compared to those ESRD renal transplant patients without an HT diagnosis. There was a significantly increased adjusted hazard ratio for graft failure in patients with a HT diagnosis compared to those without. CONCLUSION Thyroid health and HT may play a significant role in the development of the increased risk of renal transplant failure observed in this study. Additional studies are needed to investigate the underlying mechanisms for this association.
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Affiliation(s)
- B Sigman
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - D F Linder
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - J L Waller
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - W B Bollag
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA.
- Charlie Norwood VA Medical Center, Augusta, GA, USA.
| | - S L Baer
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
- Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - S Tran
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - M Kheda
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
- Southwest Georgia Nephrology, Albany, GA, USA
| | - L Young
- College of Nursing at Augusta University, Augusta, GA, USA
| | - A Mohammed
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - C M Isales
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - B Siddiqui
- Medical College of Georgia at Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
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Adithya-Sateesh B, Gousy N, Thimmanayakanahalli RSS, Tran S, Atalay RT, Michael MB. Orbital B-cell Lymphoma Masquerading As Dry Eye Disease. Cureus 2023; 15:e37228. [PMID: 37168180 PMCID: PMC10166282 DOI: 10.7759/cureus.37228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 04/05/2023] [Indexed: 04/08/2023] Open
Abstract
Orbital lymphoma is a rare tumor with an incidence of 2.02 per million per year. It can occur as a part of systemic lymphoma or spontaneously arise primarily in orbit. The most commonly reported malignant lymphoma is non-Hodgkin's lymphoma. The typical clinical finding includes exophthalmos, swelling, and limited eye movement. Our patient presented with dryness and irritation of the eye without signs of proptosis until months later. The definitive diagnosis of orbital lymphoma requires a biopsy. Still, imaging studies such as MRI and CT scans play a critical role in distinguishing benign from malignant lesions and invasion of local tissues. The treatment of orbital lymphoma is multidisciplinary, involving surgical resection, radiotherapy, and chemotherapy depending on the histological type of tumor and the presence of metastasis.
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Cobes N, Tran S, Bielle F, Touat M, Kas A, Rozenblum L. Étude de l’expression de LAT-1 et de la fixation de la 18F-FDOPA dans les tumeurs cérébrales. Illustration par une série de cas. Médecine Nucléaire 2023. [DOI: 10.1016/j.mednuc.2022.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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Valyraki N, Maillart E, Pourcher V, Shor N, Tran S, Boudot de la Motte M, Houiller C, Domont F, Morvan E, Touat M, Del Mar Amador M, Aboab J, Mathon B, Hesters A, Vignal-Clermont C, Dehais C, Bonnin S, Lafitte F, Villain N, Varnous S, Gout O, Eloit M, Rodriguez C, Deschamps R. Human pegivirus identified in severe myelitis and optic neuritis in immunocompromised patients: A pathogenic role for a forgotten virus? Rev Neurol (Paris) 2022; 179:361-367. [PMID: 36302709 DOI: 10.1016/j.neurol.2022.06.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 05/11/2022] [Accepted: 06/08/2022] [Indexed: 11/05/2022]
Abstract
The role of Human pegivirus (HPgV) in patients with encephalitis has been recently questioned. We present cases of 4 patients with similar clinical, biological, and radiological characteristics, including a past history of transplantation with long-term immunosuppression and a progressive course of severe and predominantly myelitis, associated in 3 cases with optic neuropathy causing blindness. Extensive workup was negative but analysis of the CSF by use of pan-microorganism DNA- and RNA-based shotgun metagenomics was positive for HPgV. This case series further supports the hypothesis of HPgV CNS infection and highlights the utility of metagenomic next-generation sequencing of CSF in immunocompromised patients.
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Tran S, Thomas A, Touat M, Karachi C, Lozano F, Mokhtari K, Dehais C, Feuvret L, Carpentier C, Giry M, Doukani H, Lerond J, Marie Y, Sanson M, Idbaih A, Carpentier A, Hoang-Xuan K, Capelle L, Bielle F. OS07.1.A A threshold of mitotic activity and post-surgery residual volume are independant prognostic factors in astrocytoma IDH-mutant. Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac174.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The distinction between grade 2 and 3 is instrumental to choose between observational follow-up and adjuvant treatment in resected astrocytoma IDH-mutant. However, criteria of grade 2 versus 3 have not been updated since the WHO 2007 classification. There is no consensus on the method of evaluation of the mitotic activity or a cut-off of mitoses separating grade 2 and grade 3 tumors. The objectives were to evaluate the maximal mitotic activity on a series of resected astrocytoma IDH-mutant and assess its prognostic impact on survival.
Material and Methods
Maximal mitotic activity on consecutive high power fields corresponding to 3 mm2 was examined in 118 lower-grade astrocytoma IDH-mutant. The prognostic value for time-to-treatment (TTT) and overall survival (OS) of mitotic activity and other putative prognostic factors (including age, performance status, pre-surgical tumor volume, plurilobar involvement, post-surgical residual tumor volume, midline involvement) was assessed in tumors with (i) ATRX loss, and (ii) without CDKN2A homozygous deletion, lesional enhancement, histological necrosis nor microvascular proliferation.
Results
Among the 75 (64%) of tumors which had gone through observational follow-up after resection, the maximal mitotic activity, the post-surgical residual volume and the plurilobar involvement were independent prognostic factors of TTT (p < 0.0001). A threshold of mitotic activity for grade 2 was fitted on TTT and OS prognosis. Using this threshold, patients with “grade 2 tumors” had a median TTT of 55 months versus 19 months for “grade 3” (p = 0.0057) and a median OS of 102 months versus 73 months respectively (p = 0.001). Residual volume < 1 cm3 was associated with longer OS (113 months versus 88 months, p = 0.0021).
Conclusion
Mitotic activity and post-surgical residual volume can be combined to evaluate prognosis in resected astrocytoma IDH-mutant and could select the best candidates for observational follow-up.
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Affiliation(s)
- S Tran
- Pitie-Salpetriere Hospital, Department of Neuropathology , Paris , France
| | - A Thomas
- Institut de Cancérologie Strasbourg Europe, Department of Radiation Oncology , Strasbourg , France
| | - M Touat
- Pitie-Salpetriere Hospital, Department of Neurology Mazarin , Paris , France
| | - C Karachi
- Pitie-Salpetriere Hospital, Department of Neurosurgery , Paris , France
| | - F Lozano
- Pitie-Salpetriere Hospital, Department of Neurology Mazarin , Paris , France
| | - K Mokhtari
- Pitie-Salpetriere Hospital, Department of Neuropathology , Paris , France
| | - C Dehais
- Pitie-Salpetriere Hospital, Department of Neurology Mazarin , Paris , France
| | - L Feuvret
- Pitie-Salpetriere Hospital, Department of Radiotherapy , Paris , France
| | - C Carpentier
- Sorbonne Universite, Paris Brain Institute - ICM , Paris , France
| | - M Giry
- Sorbonne Universite, Paris Brain Institute - ICM , Paris , France
| | - H Doukani
- Sorbonne Universite INSERM, Plateforme post-genomique de la Pitie-Salpetriere , Paris , France
| | - J Lerond
- Sorbonne Universite, Paris Brain Institute - ICM , Paris , France
| | - Y Marie
- Sorbonne Universite, Paris Brain Institute - ICM , Paris , France
| | - M Sanson
- Pitie-Salpetriere Hospital, Department of Neurology Mazarin , Paris , France
| | - A Idbaih
- Pitie-Salpetriere Hospital, Department of Neurology Mazarin , Paris , France
| | - A Carpentier
- Pitie-Salpetriere Hospital, Department of Neurosurgery , Paris , France
| | - K Hoang-Xuan
- Pitie-Salpetriere Hospital, Department of Neurology Mazarin , Paris , France
| | - L Capelle
- Pitie-Salpetriere Hospital, Department of Neurosurgery , Paris , France
| | - F Bielle
- Pitie-Salpetriere Hospital, Department of Neuropathology , Paris , France
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Voortman L, Anderson C, Urban E, Yuan L, Tran S, Neuhaus-Follini A, Derrick J, Gregor T, Johnston RJ. Temporally dynamic antagonism between transcription and chromatin compaction controls stochastic photoreceptor specification in flies. Dev Cell 2022; 57:1817-1832.e5. [PMID: 35835116 PMCID: PMC9378680 DOI: 10.1016/j.devcel.2022.06.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 05/09/2022] [Accepted: 06/20/2022] [Indexed: 01/12/2023]
Abstract
Stochastic mechanisms diversify cell fates during development. How cells randomly choose between two or more fates remains poorly understood. In the Drosophila eye, the random mosaic of two R7 photoreceptor subtypes is determined by expression of the transcription factor Spineless (Ss). We investigated how cis-regulatory elements and trans factors regulate nascent transcriptional activity and chromatin compaction at the ss gene locus during R7 development. The ss locus is in a compact state in undifferentiated cells. An early enhancer drives transcription in all R7 precursors, and the locus opens. In differentiating cells, transcription ceases and the ss locus stochastically remains open or compacts. In SsON R7s, ss is open and competent for activation by a late enhancer, whereas in SsOFF R7s, ss is compact, and repression prevents expression. Our results suggest that a temporally dynamic antagonism, in which transcription drives large-scale decompaction and then compaction represses transcription, controls stochastic fate specification.
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Affiliation(s)
- Lukas Voortman
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Caitlin Anderson
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Elizabeth Urban
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Luorongxin Yuan
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Sang Tran
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | | | - Josh Derrick
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Thomas Gregor
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA; Joseph Henry Laboratories of Physics, the Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Developmental and Stem Cell Biology, UMR3738, Institut Pasteur, 75015 Paris, France
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA.
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Mohammed ISK, Tran S, Toledo-Espiett LA, Munir WM. The detection of keratoconus using novel metrics derived by anterior segment optical coherence tomography. Int Ophthalmol 2022; 42:2117-2126. [PMID: 34989951 DOI: 10.1007/s10792-021-02210-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 12/24/2021] [Indexed: 12/19/2022]
Abstract
PURPOSE To determine through a feasibility study whether anterior and posterior corneal arc length and cross-sectional area measured using anterior segment ocular coherence tomography (AS-OCT) can distinguish between healthy and keratoconic corneas. METHODS Patients diagnosed with keratoconus along with healthy controls underwent AS-OCT. ImageJ was used to determine the central 6 mm anterior and posterior corneal arc lengths and cross-sectional areas. Each length and area was then divided into 1-mm segment and relative differences compared. RESULTS Twenty-five eyes from 15 patients with keratoconus, along with 25 eyes from 14 healthy controls were enrolled. There was a statistically significant difference in anterior and posterior corneal arc lengths as well as corneal cross-sectional area (p = 0.006, p = 0.005, p = 0.01, respectively). When selecting for the less advanced keratoconus eye, it was noted that posterior corneal arc length was longer in the paracentral temporal segment (1003 vs. 1010 µm, p = 0.04) and that greater change in corneal cross-sectional areas occurred between adjacent segments in less advanced keratoconus eyes. CONCLUSION AS-OCT is capable of reliably measuring corneal arc lengths in patients with keratoconus and healthy patients. Both anterior and posterior corneal arc lengths along with central cross-sectional areas are statistically different between healthy and keratoconus eyes.
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Affiliation(s)
- Isa S K Mohammed
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, 419 W Redwood Street, Suite 470, Baltimore, MD, 21201, USA
| | - Sang Tran
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, 419 W Redwood Street, Suite 470, Baltimore, MD, 21201, USA
| | - Luis A Toledo-Espiett
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, 419 W Redwood Street, Suite 470, Baltimore, MD, 21201, USA
| | - Wuqaas M Munir
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, 419 W Redwood Street, Suite 470, Baltimore, MD, 21201, USA.
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Jung J, Bollag W, Waller J, Tran S, Baer S, Kheda M, Mohammed A, Padala S, Young L, Siddiqui B. 239 Cutaneous squamous cell carcinoma and mortality in end stage renal disease. J Invest Dermatol 2021. [DOI: 10.1016/j.jid.2021.02.261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Siddiquee N, Waller J, Baer S, Kheda M, Mohammed A, Padala S, Siddiqui B, Young L, Tran S, Bollag W. 235 Association of stroke with psoriasis in end-stage renal disease patients. J Invest Dermatol 2021. [DOI: 10.1016/j.jid.2021.02.257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Kim JY, Tran S, Gunraj C, Nankoo JF, Wang Y, Rinchon C, Drummond N, Chen R. Effects of primary sensory cortex intermittent theta burst stimulation on motor cortex excitability. Parkinsonism Relat Disord 2020. [DOI: 10.1016/j.parkreldis.2020.06.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Tran S, Kim J, Gunraj C, Nankoo J, Wang Y, Drummond N, Chen R. P68 Effects of intermittent theta burst stimulation of the primary somatosensory cortex on sensory and motor cortex excitability. Clin Neurophysiol 2020. [DOI: 10.1016/j.clinph.2019.12.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Wang Y, Fomenko A, Nankoo J, Tran S, Zeng K, Drummond N, Lozano A, Chen R. P205 Inhibitory effects of low-intensity focused ultrasound stimulation on the contralateral primary motor cortex. Clin Neurophysiol 2020. [DOI: 10.1016/j.clinph.2019.12.316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Viets K, Sauria MEG, Chernoff C, Rodriguez Viales R, Echterling M, Anderson C, Tran S, Dove A, Goyal R, Voortman L, Gordus A, Furlong EEM, Taylor J, Johnston RJ. Characterization of Button Loci that Promote Homologous Chromosome Pairing and Cell-Type-Specific Interchromosomal Gene Regulation. Dev Cell 2019; 51:341-356.e7. [PMID: 31607649 DOI: 10.1016/j.devcel.2019.09.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 06/07/2019] [Accepted: 09/09/2019] [Indexed: 01/05/2023]
Abstract
Homologous chromosomes colocalize to regulate gene expression in processes including genomic imprinting, X-inactivation, and transvection. In Drosophila, homologous chromosomes pair throughout development, promoting transvection. The "button" model of pairing proposes that specific regions along chromosomes pair with high affinity. Here, we identify buttons interspersed across the fly genome that pair with their homologous sequences, even when relocated to multiple positions in the genome. A majority of transgenes that span a full topologically associating domain (TAD) function as buttons, but not all buttons contain TADs. Additionally, buttons are enriched for insulator protein clusters. Fragments of buttons do not pair, suggesting that combinations of elements within a button are required for pairing. Pairing is necessary but not sufficient for transvection. Additionally, pairing and transvection are stronger in some cell types than in others, suggesting that pairing strength regulates transvection efficiency between cell types. Thus, buttons pair homologous chromosomes to facilitate cell-type-specific interchromosomal gene regulation.
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Affiliation(s)
- Kayla Viets
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Michael E G Sauria
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Chaim Chernoff
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | | | - Max Echterling
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Caitlin Anderson
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Sang Tran
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Abigail Dove
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Raghav Goyal
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Lukas Voortman
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Andrew Gordus
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Eileen E M Furlong
- European Molecular Biology Laboratory, Department of Genome Biology, Heidelberg 69117, Germany
| | - James Taylor
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA.
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Hutton J, Doyle J, Zordan R, Weiland T, Cocco A, Howell J, Iser S, Snell J, Fry S, New K, Sloane R, Jarman M, Phan D, Tran S, Pedrana A, Williams B, Johnson J, Glasgow S, Thompson A. Point-of-care Hepatitis C virus testing and linkage to treatment in an Australian inner-city emergency department. Int J Drug Policy 2019; 72:84-90. [PMID: 31351752 DOI: 10.1016/j.drugpo.2019.06.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 06/20/2019] [Accepted: 06/23/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND In Australia, Hepatitis C Virus (HCV) treatment is declining, despite broad access to direct-acting antiviral medication. People who inject drugs are proportionally over-represented in emergency department presentations. Emergency department assessment of people who have injected drugs for HCV presents an opportunity to engage this marginalised population with treatment. We describe the outcomes of risk-based screening and point-of-care anti-HCV testing for emergency department patients, and linkage to outpatient antiviral treatment. METHODS During the three-month study period, consecutive adult patients who presented to the emergency department during the study times were screened for risk factors and offered the OraQuick oral HCV antibody test. Those with reactive results were offered venepuncture in the emergency department for confirmatory testing and direct-acting antiviral treatment in clinic. The main outcome measures were the number and proportion of viremic participants that were linked to the hepatitis clinic, commenced treatment and achieved a sustained viral response. Secondary outcome measures were the proportion (%) of presentations screened that were oral antibody reactive, and the prevalence and type of HCV risk factors. RESULTS During the study period, 2408 of the 3931 (61%) presentations to the emergency department were eligible for screening. Of these 2408 patients, 1122 (47%) participated, 307 (13%) declined participation and 977 (41%) could not be approached during their time in the emergency department. Among the 1122 participants, 378 (34%) reported at least one risk factor. Subsequently, 368 (97%) of the 378 participants underwent OraQuick anti-HCV test, and 50 (14%) had a reactive result. A risk factor of ever having injected drugs was present in 44 (88%) of participants who were sero-positive. Of the 45 that had blood tested, 30 (67%) were HCV ribonucleic acid (RNA) positive. Three participants died. Of the 27 remaining participants, 10 (37%) commenced treatment and 7 of these 10 (70%) obtained a cure. There was a high rate of homelessness (24%) among anti-HCV positive participants. CONCLUSION Among emergency department participants with a risk factor for HCV, positive serology was common using a rapid point-of-care test. A history of injecting drug use was identified as the risk factor with highest yield for positive HCV serology, and is suitable as a single screening question. However, linkage to care post ED presentation was low in this marginalised population. There is a need for new pathways to improve the care cascade for marginalised individuals living with HCV infection.
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Affiliation(s)
- J Hutton
- Emergency Department, St Vincent's Hospital Melbourne, Australia; Emergency Practice Innovation Centre, St Vincent's Hospital Melbourne, Australia.
| | - J Doyle
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; Burnet Institute, Melbourne, Australia; The Alfred and Monash University Department of Infectious Diseases, Melbourne, Australia
| | - R Zordan
- Emergency Practice Innovation Centre, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - T Weiland
- Emergency Practice Innovation Centre, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - A Cocco
- Emergency Department, St Vincent's Hospital Melbourne, Australia; Emergency Practice Innovation Centre, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - J Howell
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; Burnet Institute, Melbourne, Australia
| | - S Iser
- Emergency Department, St Vincent's Hospital Melbourne, Australia; Emergency Practice Innovation Centre, St Vincent's Hospital Melbourne, Australia
| | - J Snell
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - S Fry
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia
| | - K New
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia
| | - R Sloane
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia
| | - M Jarman
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - D Phan
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - S Tran
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
| | - A Pedrana
- Burnet Institute, Melbourne, Australia
| | | | - J Johnson
- Australian Research Centre in Sex, Health and Society, La Trobe University, Melbourne, Australia
| | - S Glasgow
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia
| | - A Thompson
- Gastroenterology Department, St Vincent's Hospital Melbourne, Australia; University of Melbourne, Melbourne, Australia
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Lewis J, Zarate M, Tran S, Albertson T. The Recommendation and Use of Extracorporeal Membrane Oxygenation (ECMO) in Cases Reported to the California Poison Control System. J Med Toxicol 2019; 15:169-177. [PMID: 30895517 DOI: 10.1007/s13181-019-00704-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 01/21/2023] Open
Abstract
INTRODUCTION Antidotes are available to treat some specific poisonings; however, the mainstay of treatment for the poisoned patient remains supportive care. Extracorporeal membrane oxygenation (ECMO) is one of the most aggressive supportive measures available to manage poisoned patients. OBJECTIVE To characterize the recommendation and use of ECMO in cases reported to the California Poison Control System (CPCS). METHODS This retrospective chart review queried the CPCS database from 1997 to 2016 for cases containing the American Association of Poison Control Centers (AAPCC) code for ECMO, and "ECMO" and "ECLS" free-text searches. The collected data included year, age, gender, substances involved, route of exposure, clinical effects, treatments, and medical outcome. RESULTS A total of 94 cases discussed ECMO as a supportive option with 16 cases utilizing ECMO. Cases where ECMO was discussed rose from one case in 1997 to 13 cases in 2016. Of the 94 cases where ECMO was discussed, 38 cases (40%) involved toxicity from a cardiovascular agent(s) and 33 cases (35%) involved exposure to hydrocarbons. Of the 16 cases where ECMO was performed, 13 (81%) involved males. The median age was 17 years (range 1 month-54 years). Ten cases (63%) involve patients under the age of 18. In this series, 13 of 16 ECMO-supported patients survived (81%). CONCLUSIONS ECMO is being recommended more often for treatment of acute poisoning cases by the CPCS. All caregivers involved in the treatment of poisoning should gain a working knowledge of the potentially lifesaving technology of ECMO, its indications for use, adverse effects, and drug or poison interactions.
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Affiliation(s)
- Justin Lewis
- California Poison Control System (CPCS), Sacramento Division, 2450 48th St. ASB 1260, Sacramento, CA, 95817, USA.
- School of Pharmacy, University of California San Francisco, San Francisco, CA, USA.
- School of Medicine, University of California Davis, Sacramento, CA, USA.
| | - M Zarate
- California Poison Control System (CPCS), Sacramento Division, 2450 48th St. ASB 1260, Sacramento, CA, 95817, USA
- School of Pharmacy, University of California San Francisco, San Francisco, CA, USA
| | - S Tran
- California Poison Control System (CPCS), Sacramento Division, 2450 48th St. ASB 1260, Sacramento, CA, 95817, USA
- School of Pharmacy, University of California San Francisco, San Francisco, CA, USA
| | - T Albertson
- California Poison Control System (CPCS), Sacramento Division, 2450 48th St. ASB 1260, Sacramento, CA, 95817, USA
- School of Pharmacy, University of California San Francisco, San Francisco, CA, USA
- School of Medicine, University of California Davis, Sacramento, CA, USA
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Sichez P, Boissier R, Delaporte V, Karsenty G, Lechevallier E, Ben Othman K, Tran S, Moal V. Altération de la fonction rénale après néphrectomie, comparaison de 3 populations : néphrectomie pour don vivant, néphrectomie élargie et néphrectomie partielle pour cancer. Prog Urol 2017. [DOI: 10.1016/j.purol.2017.07.192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Bennett G, Tran S, Richmond J, Thompson A. P8 Using ‘teach-back’ with clients who live with chronic hepatitis B: does it improve understanding? J Virus Erad 2017. [DOI: 10.1016/s2055-6640(20)30749-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Hay M, Mercer AM, Lichtwark I, Tran S, Hodgson WC, Aretz HT, Armstrong EG, Gorman D. Selecting for a sustainable workforce to meet the future healthcare needs of rural communities in Australia. Adv Health Sci Educ Theory Pract 2017; 22:533-551. [PMID: 27804091 DOI: 10.1007/s10459-016-9727-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/26/2016] [Indexed: 05/14/2023]
Abstract
An undersupply of generalists doctors in rural communities globally led to widening participation (WP) initiatives to increase the proportion of rural origin medical students. In 2002 the Australian Government mandated that 25% of commencing Australian medical students be of rural origin. Meeting this target has largely been achieved through reduced standards of entry for rural relative to urban applicants. This initiative is based on the assumption that rural origin students will succeed during training, and return to practice in rural locations. One aim of this study was to determine the relationships between student geographical origin (rural or urban), selection scores, and future practice intentions of medical students at course entry and course exit. Two multicentre databases containing selection and future practice preferences (location and specialisation) were combined (5862), representing 54% of undergraduate medical students commencing from 2006 to 2013 across nine Australian medical schools. A second aim was to determine course performance of rural origin students selected on lower scores than their urban peers. Selection and course performance data for rural (461) and urban (1431) origin students commencing 2006-2014 from one medical school was used. For Aim 1, a third (33.7%) of rural origin students indicated a preference for future rural practice at course exit, and even fewer (6.7%) urban origin students made this preference. Results from logistic regression analyses showed significant independent predictors were rural origin (OR 4.0), lower Australian Tertiary Admissions Rank (ATAR) (OR 2.1), or lower Undergraduate Medical and Health Sciences Admissions Test Section 3 (non-verbal reasoning) (OR 1.3). Less than a fifth (17.6%) of rural origin students indicated a preference for future generalist practice at course exit. Significant predictors were female gender (OR 1.7) or lower ATAR (OR 1.2), but not rural origin. Fewer (10.5%) urban origin students indicated a preference for generalist practice at course exit. For Aim 2, results of Mann-Whitney U tests confirmed that slightly reducing selection scores does not result in increased failure, or meaningfully impaired performance during training relative to urban origin students. Our multicentre analysis supports success of the rural origin WP pathway to increase rural student participation in medical training. However, our findings confirm that current selection initiatives are insufficient to address the continuing problem of doctor maldistribution in Australia. We argue for further reform to current medical student selection, which remains largely determined by academic meritocracy. Our findings have relevance to the selection of students into health professions globally.
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Affiliation(s)
- M Hay
- Monash Institute for Health and Clinical Education, Faculty of Medicine, Nursing, and Health Sciences, Monash University, 27 Rainforest Walk, Clayton, VIC, Australia.
| | - A M Mercer
- Faculty of Medicine, Dentistry and Health Sciences, University of Western Australia, Perth, Australia
| | - I Lichtwark
- Monash Institute for Health and Clinical Education, Faculty of Medicine, Nursing, and Health Sciences, Monash University, 27 Rainforest Walk, Clayton, VIC, Australia
| | - S Tran
- Monash Institute for Health and Clinical Education, Faculty of Medicine, Nursing, and Health Sciences, Monash University, 27 Rainforest Walk, Clayton, VIC, Australia
| | - W C Hodgson
- Monash Institute for Health and Clinical Education, Faculty of Medicine, Nursing, and Health Sciences, Monash University, 27 Rainforest Walk, Clayton, VIC, Australia
| | - H T Aretz
- Partners Healthcare, Boston, MA, USA
| | - E G Armstrong
- Harvard Macy Institute, Harvard Medical School, Boston, MA, USA
| | - D Gorman
- University of Auckland, Auckland, New Zealand
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Yan J, Anderson C, Viets K, Tran S, Goldberg G, Small S, Johnston RJ. Regulatory logic driving stable levels of defective proventriculus expression during terminal photoreceptor specification in flies. Development 2017; 144:844-855. [PMID: 28126841 DOI: 10.1242/dev.144030] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/02/2017] [Indexed: 12/13/2022]
Abstract
How differential levels of gene expression are controlled in post-mitotic neurons is poorly understood. In the Drosophila retina, expression of the transcription factor Defective Proventriculus (Dve) at distinct cell type-specific levels is required for terminal differentiation of color- and motion-detecting photoreceptors. Here, we find that the activities of two cis-regulatory enhancers are coordinated to drive dve expression in the fly eye. Three transcription factors act on these enhancers to determine cell-type specificity. Negative autoregulation by Dve maintains expression from each enhancer at distinct homeostatic levels. One enhancer acts as an inducible backup ('dark' shadow enhancer) that is normally repressed but becomes active in the absence of the other enhancer. Thus, two enhancers integrate combinatorial transcription factor input, feedback and redundancy to generate cell type-specific levels of dve expression and stable photoreceptor fate. This regulatory logic may represent a general paradigm for how precise levels of gene expression are established and maintained in post-mitotic neurons.
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Affiliation(s)
- Jenny Yan
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA
| | - Caitlin Anderson
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA
| | - Kayla Viets
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA
| | - Sang Tran
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA
| | - Gregory Goldberg
- Center for Developmental Genetics, Department of Biology, New York University, 100 Washington Square East, New York, NY 10003-6688, USA
| | - Stephen Small
- Center for Developmental Genetics, Department of Biology, New York University, 100 Washington Square East, New York, NY 10003-6688, USA
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA
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Tran S, Niyomthong P, McCaughan F, Hardavella G, Warwick G, Whitaker D, Desai S. 112: Microwave ablation of malignant lung lesions – the King's experience. Lung Cancer 2017. [DOI: 10.1016/s0169-5002(17)30162-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Strong C, Hur K, Kim F, Pan J, Tran S, Juon HS. Sociodemographic characteristics, knowledge and prevalence of viral hepatitis infection among Vietnamese Americans at community screenings. J Immigr Minor Health 2016; 17:298-301. [PMID: 24715472 DOI: 10.1007/s10903-014-0015-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Few studies have investigated the prevalence of hepatitis B virus (HBV) and C virus (HCV) infection among Vietnamese Americans (VAs). The purpose of this paper is to assess the prevalence of HBV and HCV infection, identify the sociodemographic characteristics of the HBV infected population and the level of HBV knowledge among VAs in the Baltimore-Washington metropolitan areas with data from a health fair in 2011. A total of 617 VAs received serological testing for HBV and HCV, and 329 completed a survey of HBV knowledge assessment. About 9% were infected with HBV and 5% with HCV. Vietnamese Americans younger than 30 years had the highest HBV prevalence (13.1%) followed by those age 41-50 years (12.1%). The prevalence of HCV infection was particularly higher among those older than 70 years old (13.9%). Misunderstanding HBV as a food-borne disease is prevalent among VAs. Efforts to develop public health screening and education programs targeting this population are warranted.
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Affiliation(s)
- Carol Strong
- Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Tran S, Facciol A, Gerlai R. The Zebrafish, a Novel Model Organism for Screening Compounds Affecting Acute and Chronic Ethanol-Induced Effects. International Review of Neurobiology 2016; 126:467-84. [DOI: 10.1016/bs.irn.2016.02.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Tran S, Lechevallier E. Intérêt de la conservation rénale en milieu saturé en argon, en normothermie et en hypothermie chez le rat. Prog Urol 2014; 24:801. [DOI: 10.1016/j.purol.2014.08.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tran S, Rousseau C, Brétel F, Guillin O, Haouzir S, Bourgeois V. P-248 - A bipolar affective disorder prior to the unset of a multiple sclerosis: a case report. Eur Psychiatry 2012. [DOI: 10.1016/s0924-9338(12)74415-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Kallman JB, Tran S, Arsalla A, Haddad D, Stepanova M, Fang Y, Wrobel VJ, Srishord M, Younossi ZM. Vietnamese community screening for hepatitis B virus and hepatitis C virus. J Viral Hepat 2011; 18:70-6. [PMID: 20196807 DOI: 10.1111/j.1365-2893.2010.01278.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Asian Americans represent an important cohort at high risk for viral hepatitis. To determine the prevalence of Hepatitis B virus (HBV) and Hepatitis C virus (HCV) infection and HBV vaccination in a Vietnamese community, a total of 322 Vietnamese subjects from a local doctor's office and annual Vietnamese Health Fair were included in this study. Demographic and clinical data were collected. 2.2% of the screened cohort tested positive for anti-HCV and 9.3% tested positive for HBsAg. Unlike HBV-positive subjects, HCV-positive subjects had significantly higher liver enzymes (P = 0.0045 and P = 0.0332, respectively). The HBV-positive group was more likely to report jaundice (P = 0.0138) and a family history of HBV (P = 0.0115) compared to HBV-negative subjects. Forty-eight patients (15.5%) reported a family history of liver disease (HBV, HCV, HCC, cirrhosis, other). Of this 48, 68.8% reported no personal history of HBV vaccination and 77.1% reported no family history of vaccination for HBV. Among the 183 subjects without a family history of liver disease, 156 (85.2%) reported no personal history of vaccination and 168 (91.8%) reported no family history of vaccination. HBV vaccination rates in those reporting a family history of liver disease were significantly higher (P =0.020). There was a high prevalence of HBV infection in this community screening. Nevertheless, the rate for HBV vaccination was low. The low prevalence of abnormal liver enzymes in HBV-positive subjects emphasizes the need for screening to be triggered by risk factors and not by abnormal liver enzymes.
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Affiliation(s)
- J B Kallman
- Center for Liver Diseases Outcomes Research Program, Inova Fairfax Hospital, Betty and Guy Beatty Center for Integrated Research, Falls Church, VA, USA
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Stade BC, Barozzino T, Bennett D, Jeffs L, Laird H, Patterson K, Reynolds J, Sandor P, Stephens R, Tran S. The Nature of Sleep in Canadian Children with Fetal Alcohol Spectrum Disorder. Paediatr Child Health 2010. [DOI: 10.1093/pch/15.suppl_a.51aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Stade BC, Bennett D, Khuu M, Patterson K, Tran S, Kapur B. Endogenous Methanol Derived Formic Acid Correlates with Cognitive Dysfunction in Children Born to Drinking Mothers. Paediatr Child Health 2010. [DOI: 10.1093/pch/15.suppl_a.70ab] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abstract
BACKGROUND Activated protein C (APC) inhibits factor Va (FVa) by cleaving at Arg306, Arg506 and Arg679. Protein S serves as cofactor, in particular for the Arg306 site, and a protein S-mediated relocation of the active site of APC closer to the membrane has been proposed as a mechanism. Recently, it was demonstrated that FVa, which was mutated at all three APC-cleavage sites (FVa-306Q/506Q/679Q), could still be cleaved by APC. These sites were close to Arg306 and Arg506 but not further defined. OBJECTIVE To identify and characterize the additional APC-cleavage sites in FVa. METHODS The cDNA for FV-306Q/506Q/679Q was used as a template to create FV variants with one or more possible cleavage sites being mutated. The FV variants were expressed and their sensitivity for APC characterized functionally and with Western blotting. RESULTS The additional APC-cleavage sites were located at Lys309, Arg313, Arg316, Arg317 and Arg505. FVa-306Q/309Q/313Q/316Q/317Q/505Q/506Q/679Q (denoted 8M-FVa) was APC resistant. To investigate individual sites, they were mutated back using 8M-FV as a template. The kinetics of APC-degradation of these variants demonstrated that protein S was equally efficient in enhancing the APC effect for all the novel sites. CONCLUSIONS Multiple APC-cleavage sites close to Arg306 and a single site close to Arg506 were identified. Protein S was equally efficient as APC cofactor for all novel sites. The stimulation by protein S of the Arg505 cleavage argues against a specific protein S-mediated stimulation of cleavage at Arg306 due to relocation of the APC active site closer to the membrane.
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Affiliation(s)
- S Tran
- Department of Laboratory Medicine, Division of Clinical Chemistry, The Wallenberg Laboratory, Lund University, MAS, Malmo, Sweden
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Tran S, Lewalski EA, Dwyre DM, Hagar Y, Beckett L, Janatpour KA, Holland PV. Does donating blood for the first time during a national emergency create a better commitment to donating again? Vox Sang 2009; 98:e219-24. [PMID: 20002621 DOI: 10.1111/j.1423-0410.2009.01274.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND AND OBJECTIVES Emergency situations often elicit a generous response from the public. This occurred after attacks on the US on September 11, 2001 when many new blood donors lined up to donate. This study was performed to compare return rates for first time donors (FTD) after September 11th, 2001 to FTD during a comparable period in 2000. MATERIALS AND METHODS A total of 3315 allogeneic whole blood donations from FTD at a regional blood centre were collected between September 11th and 30th, 2001. Subsequent donations by the FTD before March 31, 2002 were reviewed. This (test) group was compared to 1279 FTD (control group) donating during the same time period in September 2000 and to their return rate in the subsequent 6 months. RESULTS Following September 11, 2001, 1087/3315 (32.8%) FTD returned by March 31, 2002. This return rate was similar to the control group [427/1279 (33.4%)]. The deferral rate during the donor screening process for the control group was significantly higher than the deferral rate for the September 11-30, 2001 group (P < 0.01). The odds of an individual FTD returning increased with age, and the chance of a female donor returning was 1.13 times higher than a male (P = 0.06). There was a carryover effect after September 11, 2001 too. CONCLUSION A national emergency, September 11, 2001, inspired people to donate blood for the first time. However, the proportion of return donations amongst them was not increased. Females and males in certain age groups were more likely to become repeat donors due to the residual effect of September 11, 2001. Additional efforts are needed to retain eligible FTD in donor pools.
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Affiliation(s)
- S Tran
- Department of Pathology and Laboratory Medicine, University of California-Davis Medical Center, 4400 V Street, Sacramento, CA 95817, USA
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Brezniceanu ML, Liu F, Wei CC, Tran S, Sachetelli S, Zhang SL, Guo DF, Filep JG, Ingelfinger JR, Chan JSD. Catalase overexpression attenuates angiotensinogen expression and apoptosis in diabetic mice. Kidney Int 2007; 71:912-23. [PMID: 17342175 DOI: 10.1038/sj.ki.5002188] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Increased generation of reactive oxygen species (ROS) leads to oxidative stress in diabetes. Catalase is a highly conserved heme-containing protein that reduces hydrogen peroxide to water and oxygen and is an important factor decreasing cellular injury owing to oxidative stress. Hyperglycemic conditions increase oxidative stress and angiotensinogen gene expression. Angiotensinogen conversion to angiotensin II leads to a furtherance in oxidative stress through increased generation of reactive oxygen species. In this study, we utilized mice transgenically overexpressing rat catalase in a kidney-specific manner to determine the impact on ROS, angiotensinogen and apoptotic gene expression in proximal tubule cells of diabetic animals. Proximal tubules isolated from wild-type and transgenic animals without or with streptozotocin-induced diabetes were incubated in low glucose media in the absence or presence of angiotensin II or in a high-glucose media. Our results show that the overexpression of catalase prevents the stimulation of ROS and angiotensinogen mRNA in tubules owing to elevated glucose or angiotensin II in vitro. Additionally, overexpression of catalase attenuated ROS generation, angiotensinogen and proapoptotic gene expression and apoptosis in the kidneys of diabetic mice in vivo. Our studies point to an important role of ROS in the pathophysiology of diabetic nephropathy.
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Affiliation(s)
- M-L Brezniceanu
- Research Centre, Centre hospitalier de l'Université de Montréal (CHUM)-Hôtel-Dieu, Montreal, Quebec, Canada
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Chen YW, Liu F, Tran S, Zhu Y, Hébert MJ, Ingelfinger JR, Zhang SL. Reactive oxygen species and nuclear factor-kappa B pathway mediate high glucose-induced Pax-2 gene expression in mouse embryonic mesenchymal epithelial cells and kidney explants. Kidney Int 2006; 70:1607-15. [PMID: 16985513 DOI: 10.1038/sj.ki.5001871] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Diabetic mellitus confers a major risk of congenital malformations, and is associated with diabetic embryopathy, affecting multiple organs including the kidney. The DNA paired box-2 (Pax-2) gene is essential in nephrogenesis. We investigated whether high glucose alters Pax-2 gene expression and aimed to delineate its underlying mechanism(s) of action using both in vitro (mouse embryonic mesenchymal epithelial cells (MK4) and ex vivo (kidney explant from Hoxb7-green florescent protein (GFP) mice) approaches. Pax-2 gene expression was determined by reverse transcriptase-polymerase chain reaction, Western blotting, and immunofluorescent staining. A fusion gene containing the full-length 5'-flanking region of the human Pax-2 promoter linked to a luciferase reporter gene, pGL-2/hPax-2, was transfected into MK4 cells with or without dominant negative IkappaBalpha (DN IkappaBalpha) cotransfection. Fusion gene expression level was quantified by cellular luciferase activity. Reactive oxygen species (ROS) generation was measured by lucigenin assay. Embryonic kidneys from Hoxb7-GFP mice were cultured ex vivo. High D(+) glucose (25 mM), compared to normal glucose (5 mM), specifically induced Pax-2 gene expression in MK4 cells and kidney explants. High glucose-induced Pax-2 gene expression is mediated, at least in part, via ROS generation and activation of the nuclear factor kappa B signaling pathway, but not via protein kinase C, p38 mitogen-activated protein kinase (MAPK), and p44/42 MAPK signaling.
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Affiliation(s)
- Y-W Chen
- Université Montréal, Centre hospitalier de l'Université de Montréal (CHUM)-Hôtel-Dieu, Pavillon Masson, Montréal, Québec, Canada
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Sandler AB, Johnson DH, Brahmer J, Schiller JH, Ostland M, Gray R, Tran S, Dimery I. Retrospective study of clinical and radiographic risk factors associated with early onset, severe pulmonary hemorrhage in bevacizumab-treated patients with advanced non-small cell lung cancer (NSCLC). J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.7068] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7068 Background: Bevacizumab (BV) added to chemotherapy prolongs survival in non-squamous NSCLC, but was uncommonly associated with serious pulmonary hemorrhage (PH) (Sandler A, et al, ASCO 2005). A retrospective study was conducted to potentially identify clinical or radiographic (CT) risk factors associated with early onset (<150 days from initial treatment) PH. Methods: A broad search of the E4599 database for selected bleeding terms among BV-treated patients was conducted. Cases of PH were identified and adjudicated. Associations between baseline clinical factors and incidence of PH were evaluated in the full cohort of E4599 patients. In addition, a separate case-control analysis, using controls matched on age and sex, was conducted to evaluate baseline CT variables. Chest CTs were evaluated by blinded independent assessment of lesion location, cavitation, size of largest tumor or nodal mass, vascular involvement, presence of an endobronchial tumor, and total number of intra-thoracic lesions. Additional analyses were also conducted including cases of late-onset PH, post-baseline variables such as unconfirmed tumor response at 6 weeks (RECIST) and cavitation, and combined CT data from E4599 and an earlier Ph II trial. Results: Of 425 BV-treated pts, 10 cases of PH were identified. Of these, 7 were PH without additional complicating factors, and 6 were of early-onset. The cohort analysis of these 6 early-onset cases is presented ( table ). The case-control analysis on CT risk factors is ongoing. Conclusion: PH was an uncommon event, and based on this, no evidence was observed for an association between the baseline clinical variables and the incidence of early-onset events of PH without additional complicating factors. Conclusions for the CT variables evaluated will be presented. [Table: see text] [Table: see text]
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Affiliation(s)
- A. B. Sandler
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - D. H. Johnson
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - J. Brahmer
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - J. H. Schiller
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - M. Ostland
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - R. Gray
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - S. Tran
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
| | - I. Dimery
- Vanderbilt-Ingram Cancer Center, Nashville, TN; Johns Hopkins University, Baltimore, MD; University of Wisconsin, Madison, WI; Genentech, Inc., South San Francisco, CA; Eastern Cooperative Oncology Group, Boston, MA
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Abstract
BACKGROUND Helicobacter has been identified in isolated cases of hepato-biliary diseases, but its role in the pathogenesis of these conditions remains unclear. AIM To determine whether Helicobacter could be detected in bile obtained at endoscopic retrograde cholangiopancreatography, and to evaluate the prevalence of this infection in patients with hepato-biliary diseases. METHODS Bile was collected from 125 patients with various hepato-biliary diseases undergoing endoscopic retrograde cholangiopancreatography. Among them, 75 were diagnosed with biliary stones, 15 with pancreatico-biliary malignancies and four with primary sclerosing cholangitis. The detection of Helicobacter in DNA extracted from these bile samples was performed using Helicobacter genus-specific primers (capable of detecting 100-1000 organisms/mL). RESULTS Helicobacter was detected in all positive controls. Only three samples had polymerase chain reaction inhibitors. All remaining bile samples (122 patients with hepato-biliary diseases) were negative for Helicobacter DNA. CONCLUSIONS Helicobacter can be detected in bile samples using polymerase chain reaction. This infection, however, was not present in any of our patients diagnosed with gallstones or hepato-biliary malignancies, raising doubt as to the possible association between Helicobacter and these entities. Given the low sample size of patients with primary sclerosing cholangitis, more studies are required to determine whether an association exists with this condition.
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Affiliation(s)
- C A Fallone
- Department of Medicine, McGill University Health Centre, McGill University, West Montreal, Quebec, Canada.
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Abstract
BACKGROUND Histologic findings of diabetic nephropathy (DN) are observed in allografts of patients with pretransplant (PreTx) diabetes mellitus (DM) and in patients who develop DM posttransplant (PostTx). Patients with allograft biopsies (Bx) were retrospectively studied to determine the incidence of recurrent and de novo DN and to ascertain what, if any, risk factors predispose to histologic DN in either patient population. METHODS From the renal transplant services at four hospitals from 1992 to 2000, the authors identified all patients with PreTxDM and PostTxDM (n=81). Those with renal biopsies performed >/=18 months PostTx were classified according to the presence or absence of histologic DN (Bx-positive, n=23; Bx-negative, n=35). Patients were then subdivided into four categories-recurrent DN (n=16), de novo DN (n=7), no recurrent DN (n=27), and no de novo DN (n=8)-for analyses. RESULTS Among these 58 patients, 74.1% had PreTx and 25.9% had PostTx diabetes. Of those with histologic DN, 69.6% were recurrent DN and 30.4% were de novo DN, making de novo DN at least as likely to develop as recurrent DN. After the onset of diabetes in the de novo population, the time to development of histologic DN was similar in the recurrent and the de novo patients (6.68+/-3.86 years vs. 5.90+/-3.13 years, P=0.66) and more rapid than previously reported. Apart from a more frequent family history of hypertension in patients with allograft DN compared with those without allograft DN, known risk factors for the development of native DN did not significantly differ among patients in the four cohorts. Proposed risk factors related to transplantation did not correlate with the development of recurrent or de novo DN. CONCLUSION Among patients with histologic DN, de novo DN occurred at least as frequently as recurrent DN, and the time to onset of histologically apparent DN was more rapid than previously reported. Neither the usual clinical predictors of DN nor clinical variables related to transplantation clearly distinguished the group with DN from the group without it, potentially implicating novel mechanisms in its pathogenesis.
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Affiliation(s)
- V Bhalla
- Division of Nephrology and Hypertension, Department of Internal Medicine, Harbor-UCLA Research and Education Institute, Torrance, CA, USA
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Lai ACY, Tran S, Simmonds RS. Functional characterization of domains found within a lytic enzyme produced by Streptococcus equi subsp. zooepidemicus. FEMS Microbiol Lett 2002; 215:133-8. [PMID: 12393213 DOI: 10.1111/j.1574-6968.2002.tb11382.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Zoocin A is a lysostaphin-like streptococcolytic enzyme produced by Streptococcus equi subsp. zooepidemicus 4881 that specifically targets the cell walls of some closely related species. On the basis of sequence homology it was suggested that zoocin A was a domain-structured enzyme with the N-terminal domain responsible for catalysis (CAT) and the C-terminal domain for target recognition (SBD). Polypeptides corresponding to zoocin A (rZooA) and each of the putative domains (rCAT and rSBD) were prepared by use of recombinant technology. The biological activities of each was compared by use of a dye-release assay and a cell-binding assay. Cell wall hydrolysis was shown to be a function of CAT and target recognition a function of the SBD. Expression of the zoocin A immunity factor gene produced cell walls resistant to hydrolysis by either rZooA or its component domains, and with reduced capacity to bind rZooA and rSBD.
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Affiliation(s)
- A C-Y Lai
- Microbiology Department, University of Otago, P.O. Box 56, 9001, Dunedin, New Zealand.
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Mayo D, Karabatsos N, Scarano FJ, Brennan T, Buck D, Fiorentino T, Mennone J, Tran S. Jamestown Canyon virus: seroprevalence in Connecticut. Emerg Infect Dis 2001; 7:911-2. [PMID: 11747714 PMCID: PMC2631874 DOI: 10.3201/eid0705.017529] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Tran S, Dammak L, Larchet C, Auclair B. Bi-ionic potential through a cation exchange membrane separating two electrolyte solutions at different concentrations. Electrochim Acta 1999. [DOI: 10.1016/s0013-4686(98)00383-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Roulet M, Lucotte M, Saint-Aubin A, Tran S, Rhéault I, Farella N, De Jesus Da silva E, Dezencourt J, Sousa Passos CJ, Santos Soares G, Guimarães JR, Mergler D, Amorim M. The geochemistry of mercury in central Amazonian soils developed on the Alter-do-Chão formation of the lower Tapajós River Valley, Pará state, Brazil. Sci Total Environ 1998; 223:1-24. [PMID: 9850600 DOI: 10.1016/s0048-9697(98)00265-4] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In an oxisol-spodosol system developed on the terrestrial surface of the lower Tapajós Valley, the determination of total mercury (Hg), organic carbon (C), iron and aluminum oxy-hydroxide (Fe(cdb) and Al(cdb)) concentrations in the surface soil horizons are used to characterise the geochemical processes controlling the accumulation of Hg in soils under natural vegetation cover and in deforested and cultivated sites. Oxisols from the plateau have homogeneous and relatively high background Hg contents and burdens constituting an important natural reservoir of Hg for the region (90-210 ng/g dry wt. and 19-33 mg/m2 for the first 20 cm). The Fe(cdb) and Al(cdb) contents associated with the fine fraction (< 63 microns) of the soil suggest that oxy-hydroxides and, particularly Al-substituted Fe oxy-hydroxides, control the Hg concentrations observed in all of the soils of the study region. Consequently, the geochemistry of these minerals along the slopes governs the accumulation or the release of the Hg according to the natural evolution of the soil cover and/or following the degradation of soils by erosion after deforestation and cultivation. These observations have important implications for the interpretation of Hg contamination patterns observed in Amazonian aquatic systems that could be linked to different drainage sources of Hg from the terrestrial surface. The sandification and podzolisation that is characteristic of the evolution of numerous pedological systems in the equatorial Amazon could be responsible for exportation of the naturally accumulated Hg, as for other metals, by acidic complexation and migration to the black waters of the Amazon. In the central Amazon region, as a result of the fragility of the soil cover, deforestation and cultivation, affecting principally the superficial soil, promote the selective erosion of fine particles enriched in oxides and Hg. The erosion of soil could be responsible for an important release of Hg, transported in particulate form by drainage waters.
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Affiliation(s)
- M Roulet
- Chaire de recherche en environnement H-Q/CRSNG/UQAM, B.P. 8888, Montréal, Québec, Canada
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Pitt BR, Schwarz M, Woo ES, Yee E, Wasserloos K, Tran S, Weng W, Mannix RJ, Watkins SA, Tyurina YY, Tyurin VA, Kagan VE, Lazo JS. Overexpression of metallothionein decreases sensitivity of pulmonary endothelial cells to oxidant injury. Am J Physiol 1997; 273:L856-65. [PMID: 9357862 DOI: 10.1152/ajplung.1997.273.4.l856] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Metallothionein (MT) is a low-molecular-weight cysteine-rich protein with extensive metal binding capacity and potential nonenzymatic antioxidant activity. Despite the sensitivity of vascular endothelium to either heavy metal toxicity or oxidative stress, little is known regarding the role of MT in endothelial cells. Accordingly, we determined the sensitivity of cultured sheep pulmonary artery endothelial cells (SPAEC) that overexpressed MT to tert-butyl hydroperoxide (t-BOOH), hyperoxia, or 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN; peroxyl radical generator). Nontoxic doses of 10 microM Cd increased MT levels from 0.21 +/- 0.03 to 2.07 +/- 0.24 microg/mg and resulted in resistance to t-BOOH and hyperoxia as determined by reduction of Alamar blue or [3H]serotonin transport, respectively. SPAEC stably transfected with plasmids containing either mouse or human cDNA for MT were resistant to both t-BOOH and hyperoxia. In addition, we examined transition metal-independent, noncytotoxic AMVN-induced lipid peroxidation after metabolic incorporation of the oxidant-sensitive fluorescent fatty acid cis-parinaric acid into phospholipids and high-performance liquid chromatography separation. SPAEC that overexpressed MT after gene transfer completely inhibited peroxyl oxidation of phosphatidylserine, phosphatidylcholine, and sphingomyelin (but not phosphatidylethanolamine) noted in wild-type SPAEC. These data show for the first time that MT can 1) protect pulmonary artery endothelium against a diverse array of prooxidant stimuli and 2) directly intercept peroxyl radicals in a metal-independent fashion, thereby preventing lipid peroxidation in intact cells.
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Affiliation(s)
- B R Pitt
- Department of Pharmacology, University of Pittsburgh School of Medicine, Pennsylvania 15261, USA
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Tran S, Boot JR. Differential effects of voltage-dependent Ca2+ channels on low and high frequency mediated neurotransmission in guinea-pig ileum and rat vas deferens. Eur J Pharmacol 1997; 335:31-6. [PMID: 9371543 DOI: 10.1016/s0014-2999(97)01174-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The omega-conotoxins GVIA, MVIIA, MVIIC and SVIB reduced in a concentration-dependent manner the low frequency electrically stimulated twitch response of the guinea-pig ileum and rat vas deferens. The relative activities of the conotoxins showed some difference between the two preparations in that for ileum it was MVIIA = GVIA > MVIIC = SVIB and for the vas deferens it was MVIIA > GVIA >> SVIB > MVIIC. High frequency electrical stimulation of both preparations resulted in a neurally-mediated omega-conotoxin GVIA resistant component that was sensitive to high concentrations of either omega-conotoxin MVIIC (300 nM- 1 microM) or omega-agatoxin IVA (300 nM-1 microM) but not to omega-conotoxin MVIIA. Lower levels of either omega-conotoxin MVIIC or omega-agatoxin IVA (30-100 nM) failed to significantly affect the omega-conotoxin GVIA resistant component. This omega-conotoxin GVIA resistant component was large in the ileal preparation comprising 30-40% of the maximal response at 20 Hz but relatively small (10%) in the vas deferens. These studies revealed that the N-type voltage-dependent calcium channel (VDCCs) exclusively controls neurotransmission during low frequency stimulation but at higher frequencies there is an additional non-adrenergic, non-cholinergic (NANC) neurotransmission that appears to be regulated via Q-type VDCC.
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Affiliation(s)
- S Tran
- Eli Lilly and Co., Lilly Research Centre Ltd., Windlesham, Surrey, UK
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Ahn CY, Narayanan K, Tran S, Monstrey S, Liang MD. The use of cryopreserved microvenous allografts in the venous system without immunosuppression: an experimental study. Ann Plast Surg 1996; 37:173-7. [PMID: 8863978 DOI: 10.1097/00000637-199608000-00010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Autogenous vein grafts are currently the number one choice in microsurgical practice for managing vessel length discrepancies. A significant percentage of these grafts is used in the venous system. Allografts may serve as a viable alternative source of vein grafts. Few studies in the past have described the use of cryopreserved vein grafts (1 mm in diameter) in the venous system. In the present study, we cryopreserved the femoral veins of rats and transplanted these across rat species (ACI to Lewis) as interpositional vein grafts into a defect in the femoral vein. Short-term patencies (21 days), expressions of systemic antigenicity, histology, and scanning electron microscopic studies were performed. We obtained 100% patencies with fresh control veins and cryopreserved veins at 21 days.
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Affiliation(s)
- C Y Ahn
- Division of Plastic and Reconstructive Surgery, UCLA School of Medicine 90024-1665, USA
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45
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Freeman RB, Tran S, Lee YM, Rohrer RJ, Kaplan MM. Serum hepatitis C RNA titers after liver transplantation are not correlated with immunosuppression or hepatitis. Transplantation 1996; 61:542-6. [PMID: 8610378 DOI: 10.1097/00007890-199602270-00005] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The degree to which immunosuppression and/or rejection influences recurrent hepatitis C (HCV) after liver transplantation (LT) for end-stage HCV cirrhosis remains poorly defined. We quantified serum HCV-RNA in 84 serum samples from 28 anti-HCV-positive patients taken 223 days prior to and up to 1719 days after liver transplantation to determine if cumulative immunosuppression, rejection, or histologic recurrence correlated with HCV-RNA levels. Histologic, serum chemistry, cumulative steroid, and OKT3 and alpha-interferon (INF) dose data were collected at the time of HCV-RNA sampling. Eighteen of 24 evaluable patients (75%) had HCV-RNA detected in their sera after transplant. Eight patients had 14 rejection episodes, 9 patients received OKT3, and 5 were given INF for histologically moderate hepatitis. Five patients died - two of recurrent hepatitis C - and no retransplants were performed for recurrent hepatitis. Of the 23 survivors, 7 have histologic hepatitis - 2 with persistent ascites, and 2 with mild fibrosis. We could show no correlation between HCV-RNA levels and any of the variables examined although a trend toward increasing HCV-RNA levels with increasing numbers of rejection episodes was observed. In addition, histologic recurrence occurred more frequently for patients treated with OKT3. We conclude that the quantity of circulating viral genome is not influenced by immunosuppressive load and does not correlate with laboratory or histologic signs of recurrence. The roles that rejection, and possibly OKT3, play in the recurrence of HCV after liver transplant need further study.
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Affiliation(s)
- R B Freeman
- Division of Transplant Surgery, New England Medical Center/Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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46
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Fraser JK, Tran S, Nimer SD, Gasson JC. Characterization of nuclear factors that bind to a critical positive regulatory element of the human granulocyte-macrophage colony-stimulating factor promoter. Blood 1994; 84:2523-30. [PMID: 7919370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic growth factor that stimulates the proliferation, maturation, and functional activity of myeloid cells in peripheral blood and bone marrow. Expression of GM-CSF is tightly regulated and is limited to cells stimulated directly (T cells, macrophages) or indirectly (fibroblasts, endothelial cells) by immune challenge. Several studies of the transcriptional control of GM-CSF expression have elucidated a region of the GM-CSF promoter that mediates positive regulatory activity in a number of cell types. This region contains a direct repeat of the sequence CATTA/T that extends from nucleotides -37 to -48 upstream of the start of mRNA synthesis. Although specific DNA:protein interactions have been shown within this region, neither the nature nor the number of nuclear factors responsible for these interactions have been characterized. In this study, we use DNase I footprinting analysis to demonstrate that point mutations, which inactivate the GM-CSF promoter, disrupt DNA:protein interactions within this region. By combined electrophoretic mobility shift and ultraviolet cross-linking analysis, we have detected several protein species that bind specifically to the positive regulatory sequence.
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Marcellin P, Bernuau J, Martinot-Peignoux M, Larzul D, Xu LZ, Tran S, Bezeaud A, Guimont MC, Levardon M, Aumont P. Prevalence of hepatitis C virus infection in asymptomatic anti-HIV1 negative pregnant women and their children. Dig Dis Sci 1993; 38:2151-5. [PMID: 8261814 DOI: 10.1007/bf01299888] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The prevalence of hepatitis C virus (HCV) infection was studied prospectively in pregnant women in France and their children by detection of anti-HCV with second-generation ELISA (ELISA2). In ELISA2-positive women, anti-HCV was detected with second- and third-generation RIBA (RIBA2 and RIBA3) and serum HCV RNA was detected with PCR. Among 670 women, anti-HIV1-negative, 26 (3.9%) were positive with ELISA2. RIBA2 was positive in 13 and HCV RNA was found in 10. Ten ELISA2-positive women had a further evaluation with assessment of HCV infection in their children. Among the 10 children born to the index pregnancy, only one was positive with ELISA2 and RIBA2 but negative with RIBA3 and PCR; the nine other children were ELISA2, RIBA2, RIBA3, and PCR negative. All 26 siblings (2-16 years old), of whom 14 were born to PCR-positive mothers, were ELISA2 and RIBA2 negative. We conclude that among anti-HIV1-negative pregnant women with normal serum ALT levels, the prevalence of HCV infection is relatively high but the risk for mother-to-infant transmission of HCV seems to be low.
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Affiliation(s)
- P Marcellin
- Service d'Hépatologie, Hôpital Beaujon, Clichy, France
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48
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Wehman P, Sherron P, Kregel J, Kreutzer J, Tran S, Cifu D. Return to work for persons following severe traumatic brain injury. Supported employment outcomes after five years. Am J Phys Med Rehabil 1993; 72:355-63. [PMID: 8260128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Supported employment is a recently developed rehabilitation alternative that is being used to assist individuals with traumatic brain injury to return to work. The present study reports the results of a supported employment program that has placed 80 individuals into competitive employment during a 5-year time period. All individuals had sustained a severe traumatic brain injury; 72% of the injuries involved a motor vehicle. A mean of 6.1 years had passed since injury for all participants, who had been unconscious an average of 48 days. Neuropsychologic evaluation revealed defective cognitive functioning, which contributed to diminished employment potential. A key outcome indicator used to assess return to work capacity is the monthly employment ratio, which is computed by dividing the number of months employed during an employment phase (i.e., pre/post injury) by the total possible months an individual would have the opportunity to be employed. The monthly employment ratio increased from 13% after injury with no supported employment to 67% with supported employment services. The majority of individuals were employed in warehouse, clerical and service-related occupations. A mean of 250 staff intervention hours were required to train and provide follow-up services to program participants.
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Affiliation(s)
- P Wehman
- Rehabilitation Research and Training Center on Supported Employment, Richmond, VA
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49
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Narayanan K, Ahn C, Monstrey S, Tran S, Liang MD. The use of cryopreserved venous allografts in microvascular surgery without immunosuppression: an experimental study. J Reconstr Microsurg 1993; 9:265-70. [PMID: 8410784 DOI: 10.1055/s-2007-1006665] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Excellent patency rates are currently established in the use of autogenous veins as interposition vein grafts in microsurgical practice. Allografts may be a viable alternative source of vein grafts. Recent advances in cryobiology have enabled the controlled freezing of tissues with preservation of vital cellular elements. Although several reports have shown the successful use of cryopreserved large-vessel allografts, few have addressed cryopreservation of microvessels (1 to 2 mm in diameter). In this study, the authors have successfully cryopreserved femoral veins in a rat model and transplanted them as interposition vein grafts into arterial defects across major histocompatibility barriers (ACI to Lewis). Short-term patencies (21 days) were determined, and histologic and scanning electron microscopic analysis were performed. Patency of 100 percent was achieved in both fresh control veins and in cryopreserved veins at 21 days.
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Affiliation(s)
- K Narayanan
- Division of Plastic Surgery, University of Pittsburgh Medical Center, PA
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50
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Dunham P, Dunham F, Tran S, Akhtar N. The nonreciprocating robot: effects on verbal discourse, social play, and social referencing at two years of age. Child Dev 1991; 62:1489-502. [PMID: 1786730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
2-year-old children interacted with a robot in a large playroom while their mother sat quietly in the corner. Identical vocalizations from the robot had very different effects on 3 dimensions of the children's behavior when the vocalizations were embedded in reciprocating and nonreciprocating social structures. The reciprocating robot produced (1) more topic-maintaining verbal dialogue, (2) less physical and more linguistically mediated social play, and (3) gender-specific effects on the children's tendency to visually reference their mother during the play session. The data are discussed with reference to the frequently encountered assumption that reciprocal social structures have an impact on children's behavior when the quantity and other qualitative dimensions of social stimulation are held constant, and with reference to the children's attributions about the robot as a social partner.
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Affiliation(s)
- P Dunham
- Department of Psychology, Dalhousie University, Halifax, Nova Scotia, Canada
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